Your baby’s head and body finally develop the proportions of a newborn (her noggin is no longer bigger than her belly!).

The surface of your baby’s brain begins to wrinkle (the wrinkles are called convolutions) so that it can hold more brain cells.

Your belly's increasing size is a definite clue that your baby is getting bigger every day — now he’s weighing in at about three pounds. He’ll be packing on the weight at a rate of half a pound per week for the next seven weeks.

Baby's Brain is Getting Bigger

Also growing at a quick pace these days?Baby's brain. Until now, its surface was smooth — but now, your fetus' brain is taking on those characteristic grooves and indentations. The reason for the different appearance: Those wrinkles allow for an increased amount of brain tissue — a necessary change as your baby prepares to develop street smarts for life outside your womb.

Lanugo Is Disappearing

Now that baby’s brain and new fat cells are regulating his body temperature, the lanugo — that soft, downy hair covering your little bean's body — is beginning to disappear (no need for that furry coat anymore). But you may see a few leftover strands of fur on your newborn's back and shoulders when he’s born.

Bone Marrow Is Making Red Blood Cells

Another big change at 30 weeks pregnant: Your baby's bone marrow has completely taken over production of red blood cells (before, tissue groups and then the spleen took care of producing the blood cells). This is an important step for your baby because it means she'll be better able to thrive on her own once she's born.

Heartburn

These days you may feel as though you've got a flamethrower in your chest. Indigestion is one of the most common (and annoying) pregnancy ailments. Here's why: The same pregnancy hormones that cause your body's pelvic muscles to relax so you can deliver your baby also relax the ring of muscle that separates the esophagus from the stomach. The result: Food and digestive juices can head upstream from your tummy into your chest and throat — hence, the infernal inferno. Your expanding uterus, now exerting pressure on your stomach, only fuels the fire.

So how do you spell relief? Among other things, avoid foods that can cause digestive discomfort — like spicy, fatty or fried dishes and chocolate — eat smaller meals and don't lie down while snacking or right after eating. And, of course, keep a supply of Tums or Rolaids (which also give you a healthy bonus of calcium) at popping distance. Fortunately, once your baby is born, heartburn will be a thing of the past — at least until you try to gobble dinner during a colic marathon.

Try This: Cord Blood Banking

The big day is coming, so here's a big question: What is cord blood and should you consider banking or donating your baby's? Cord blood is what remains in the umbilical cord and placenta following birth. It contains stem cells that can be used to treat some blood diseases and immune-system disorders. Promising research is under way to determine whether these stems cells can also be useful in treating other conditions, though the science is just emerging. A safe and painless procedure to collect blood is performed just after baby is born (it takes about five minutes). You can donate to a public facility for free so the cells can be used by others in need, or you can store privately for a hefty upfront fee and an annual storage cost so it's available only to your family. If you do choose to bank cord blood (and it's okay if you choose not to at all), you should talk to your practitioner about it now so the necessary prep work can be done.

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More Tips

Common Symptoms

You'll feel your baby moving every day now, sometimes with a punch or a kick (your itty-bitty boxer is getting stronger!), other times with a wiggle or stretch. You can also expect more activity after you’ve eaten and (sadly!) when you’re lying down. Baby's quarters are getting more cramped, though, so you may feel fewer hard kicks at this stage. Always check with your practitioner about any changes in fetal movement to be sure.Read more

As your uterus expands, it puts pressure on your rectum, which can weaken muscle control and lead to uncontrollable passing of gas. Drink plenty of water to avoid constipation, which aggravates the condition.Read more

Even if you managed to conquer constipation earlier in your pregnancy, you may have to contend with a return to more sluggish bowels (thank your ever-expanding uterus, which is putting pressure on them). Remember that fluids and fiber are your friends as are probiotics, which you can find in yogurt.Read more

As your skin stretches to accommodate your growing belly and body, you (and 90 percent of the pregnant set) are probably starting to see the pink or red streaks known as stretch marks. There’s no miracle cure for stretch marks, so don’t blow the bucks on expensive creams that promise to make them disappear. (Creams will soothe your itchy belly, though.)Read more

Your second trimester get-up-and-go may have up and left now. Your growing baby is putting more demands on your body, and insomnia may be leaving you pooped during the day. Now’s the time to ask for help (a skill that will come in handy after childbirth), especially while doing something strenuous.Read more

Ask Your Doctor

I leak urine when I cough or sneeze. Will this continue after delivery?

I have swelling in my ankles and legs. Is this a reason for concern? How can I reduce the swelling?

Is cord blood banking something we should consider? Can you provide us with information about it?

I’ve been having very vivid, sometimes scary, dreams about my baby. Could something be wrong?

What childbirth preparation classes do you recommend, if any?

I’ve been having a shooting pain in my lower back and butt. What is it and how do I get relief?

I’ve read I should monitor my baby’s movements twice a day. Why and how should I do this?

Are there any safety concerns I should be aware of when it comes to driving and seat belts?

When is the best time for us to discuss my birth plan?

Since we’ve found out I have gestational diabetes, what can I do to prevent type 2 diabetes in the future?

What are some of the natural pain relief options I can use during labor and delivery?

From the What to Expect editorial team and Heidi Murkoff, author of What to Expect When You’re Expecting. Health information on this site is based on peer-reviewed medical journals and highly respected health organizations and institutions including ACOG (American College of Obstetricians and Gynecologists), CDC (Centers for Disease Control and Prevention) and AAP (American Academy of Pediatrics), as well as the What to Expect books by Heidi Murkoff.

The material on this website is provided for educational purposes only and is not to be used for medical advice, diagnosis or treatment, or in place of therapy or medical care. Use of this site is subject to our terms of use and privacy policy.